A polarization beam splitter (PBS) based on an asymmetrical Mach-Zehnder interferometer (MZI) is experimentally demonstrated on a InP platform. The experimental results show that the polarization extinction ratios (PERs) are 8 dB and 14 dB for transverse-electric (TE) and transverse-magnetic (TM) polarization at 1550 nm, respectively. The PER is greater than 5 dB/12 dB for TE/TM polarization over the full C band wavelength range. Fabrication errors including the waveguide width, arm length, film thickness, and sidewall are analyzed using the beam propagation method. The width and sidewall are the most sensitive factors that affect the performances of this type of PBS. This analysis will improve the fabrication tolerance of the PBS.

基于非对称 Mach-Zehnder 干涉仪 (MZI) 的偏振分束器 (PBS) 在 InP 平台上进行了实验演示。实验结果表明，在 1550 nm 处，横向电 (TE) 和横向磁 (TM) 偏振的偏振消光比 (PER) 分别为 8 dB 和 14 dB。对于整个 C 波段波长范围内的 TE/TM 极化，PER 大于 5 dB/12 dB。使用光束传播方法分析制造误差，包括波导宽度、臂长、薄膜厚度和侧壁。宽度和侧壁是影响此类PBS性能的最敏感因素。这种分析将提高 PBS 的制造公差。